CN112484905B - High-precision pressure optical measurement method in variable temperature environment - Google Patents
High-precision pressure optical measurement method in variable temperature environment Download PDFInfo
- Publication number
- CN112484905B CN112484905B CN202011411248.9A CN202011411248A CN112484905B CN 112484905 B CN112484905 B CN 112484905B CN 202011411248 A CN202011411248 A CN 202011411248A CN 112484905 B CN112484905 B CN 112484905B
- Authority
- CN
- China
- Prior art keywords
- gas
- pressure
- temperature
- formula
- refractive index
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/04—Means for compensating for effects of changes of temperature, i.e. other than electric compensation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L11/00—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00
- G01L11/02—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00 by optical means
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention relates to a high-precision pressure optical measurement method in a variable temperature environment, and belongs to the technical field of metering tests. According to the invention, by combining two optical gas pressure measurement method models of a refractive index method and a direct absorption method in an absorption spectrum method, and by connecting two model equations, an unknown temperature variable is eliminated, and an accurate pressure value of a measured gas is solved in real time. The invention can eliminate the influence of temperature change on the pressure measurement result in real time in the variable temperature environment, and improves the pressure measurement precision.
Description
Technical Field
The invention relates to a high-precision pressure optical measurement method in a variable temperature environment, and belongs to the technical field of metering tests.
Background
Pressure is one of important parameters for mechanical measurement and testing, and is widely applied in the fields of aviation, aerospace, nuclear industry, ships, weapons and the like. In the process of testing the national defense industry, the accuracy of the pressure value directly influences the safety and the development of various fields of the national defense industry. By utilizing the advantages of high precision, high resolution, high dynamic and the like of optical measurement, the established optical pressure measurement technology is becoming a new hot spot and trend in the pressure measurement field, and important technical support is provided for realizing high-precision pressure test, high-precision pressure standard, on-site self-calibration pressure test and on-site standard in the future. The existing commonly used optical pressure measurement method is mainly based on two methods of refractive index and absorption spectrum, the pressure measurement results of the two methods are influenced by the temperature change of the gas, and how to realize high-precision measurement of the gas pressure in the environment with the temperature change is a prominent problem in the existing optical measurement of the gas pressure.
Disclosure of Invention
The invention aims to provide a high-precision pressure optical measurement method in a variable-temperature environment, which is used for realizing gas pressure optical high-precision measurement in the variable-temperature environment or establishing a high-precision pressure standard.
The purpose of the invention is realized by the following technical scheme:
a high-precision pressure optical measurement method in a variable temperature environment comprises the following steps:
measuring a gas refractive index change value by using a refractive index method, and establishing the relationship among the gas refractive index, the pressure and the temperature by using a gas state equation as follows:
p=ρRT[1+Bρ+Cρ2+Dρ3+...] (1)
in the formula: p is gas pressure, R is an ideal gas constant, T is temperature, B, C and D are first, second and third density Viry coefficients respectively, rho is medium density, and the calculation formula is as follows:
in the formula: n is the refractive index of the gas, Aε,bεThe first and second dielectric Viry coefficients, respectively.
Secondly, measuring the linear characteristic of the laser single spectral line of the measured gas by using an absorption spectrum measuring method, and establishing the relationship between the absorbance and the pressure and the temperature:
where A is the absorbance, C is the gas volume ratio, S (T) is the linear intensity of the absorption line as a function of temperature T, and L is the effective length of the gas chamber.
Step three, simultaneously establishing a formula (1) and a formula (3), eliminating the temperature T, and obtaining an equation only related to the pressure p as follows:
S-1[A/(pCL)]=p/ρR[1+Bρ+Cρ2+Dρ3+...] (4)
in the formula S-1Is an inverse function of the line intensity s (t) of the absorption line, and an accurate pressure value is obtained by solving this equation.
Advantageous effects
According to the high-precision pressure optical measurement method in the variable temperature environment, two optical gas pressure measurement method models in a refractive index method and a direct absorption method in an absorption spectrum method are combined, an unknown temperature variable is eliminated by connecting two model equations, and the accurate pressure value of the measured gas is solved in real time. The invention can eliminate the influence of temperature change on the pressure measurement result in real time in the variable temperature environment, and improves the pressure measurement precision.
Drawings
FIG. 1 is a schematic flow chart of the method of the present invention.
Detailed Description
The invention will be further described in detail with reference to the accompanying fig. 1 and examples. The present embodiment is based on the technical solution of the present invention and provides a specific implementation manner, but the scope of the present invention is not limited to the following embodiments.
The dynamic pressure distribution and measurement device has important significance for optimizing and designing the whole power system for rotary machines such as an aircraft engine air compressor, an internal combustion engine turbocharging device and the like and realizing the distribution and measurement of the dynamic pressure in a flow field at the rear end of the air compressor. Particularly, with the continuous breakthrough of the technology, the rotating speed of the rotor is continuously increased, and the problem of flow field complexity caused by high turbulence is increasingly prominent. The increase in the pressure increase ratio also causes a rapid increase in the temperature of the pressurized gaseous medium. The high coupling of high turbulence and heat transfer in a flow field causes the distribution of pressure and temperature to have the characteristics of high transient, high randomness, anisotropy and the like, which leads to the fact that the traditional pressure sensor cannot effectively eliminate the influence caused by the rapid temperature change environment, directly leads to the low precision of the measured pressure and cannot provide effective data support for the design and optimization of a power system. According to the high-precision pressure optical measurement method in the variable-temperature environment, the influence of the environmental temperature change on pressure measurement can be effectively eliminated based on a method combining a gas refractive index method and an absorption spectrum method, and the high-precision measurement of the dynamic pressure in the flow field is realized. The specific measurement procedure is described as follows:
the method comprises the following steps: and establishing a gas pressure measurement model of the measured position in the flow field based on a refractive index method.
According to the theory of electromagnetic wave propagation in space, the refractive index of gas has the following relationship with the relative permeability and dielectric constant (i.e., relative conductivity) of gas
n2=εrμr (1)
In the formula: n is the refractive index of the gas, epsilonrIs a relative dielectric constant, murIs the relative permeability, mur1, therefore: n is2=εr。
According to the Clausius-Mossotti equation and the Lorentz-Lorenz equation, the relative permittivity and the relative permeability of the nonpolar gas can be respectively expanded into the form of Viley equation according to the density:
where ρ is the density of the medium, Aε,bεAnd cεRespectively, the first, second and third dielectric virial coefficients of the dielectric. Substituting the formula for the relationship between refractive index and dielectric constant, and neglecting the higher order terms, there are:
further advancing to:
bερ2+Aερ-(n2-1)/(n2+2)=0 (4)
solving to obtain:
then according to the actual state equation of the gas, the following steps are carried out:
p=ρRT[1+Bρ+Cρ2+Dρ3+...] (6)
where p is the gas pressure, R is the ideal gas constant, T is the temperature, and B, C, and D are the first, second, and third density Viry coefficients of the medium, respectively. And (5) bringing the density formula (5) into formula (6), and establishing a relation model between the pressure p of the gas, the temperature T and the refractive index n.
Step two: and establishing a pressure measurement mathematical model of the measured position in the flow field based on the absorption spectroscopy.
According to Beer-Lambert's law, there are:
in the formula I0Is the intensity of the laser beam, ItIs the light intensity received by the detector, p is the pressure, C is the gas volume ratio,
s (T) is the line intensity of the absorption line as a function of the kelvin temperature T, L is the effective length of the gas cavity, Φ (v) is a linear function whose integral over the frequency domain is normalized, v is the laser frequency. Assuming that the parameters such as temperature, pressure and concentration in the gas chamber are uniformly distributed, there are:
wherein A is absorbance. The measurement model for the gas pressure p is thus obtained as:
step three: based on the first step and the second step, simultaneous equations (6) and (9), the temperature variable T is eliminated, and the equation only for the pressure p is obtained as follows:
S-1[A/(pCL)]=p/ρR[1+Bρ+Cρ2+Dρ3+...] (10)
and then solving the equation (10) to calculate an accurate pressure value.
Through the measurement process and the analysis and calculation, the real-time pressure measurement of the measured gas medium in the dynamic environment is accurately realized, the influence of temperature change in the measured gas medium is eliminated, the high-precision measurement of the dynamic pressure in a flow field can be realized, and more effective data support is provided for further promotion of power systems of an aeroengine compressor, an internal combustion engine, a turbine and the like.
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (1)
1. A high-precision pressure optical measurement method in a variable temperature environment is characterized by comprising the following steps: the method comprises the following steps:
measuring a gas refractive index change value by using a refractive index method, and establishing the relationship among the gas refractive index, the pressure and the temperature by using a gas state equation as follows:
p=ρRT[1+Bρρ+Cρρ2+Dρρ3+...] (1)
in the formula: p is gas pressure, R is ideal gas constant, T is temperature, Bρ ,C ρ And Dρ The first, second and third density Viry coefficients are respectively, rho is the medium density, and the calculation formula is as follows:
in the formula: n is the refractive index of the gas, Aε,bεFirst and second dielectric Viry coefficients, respectively;
secondly, measuring the linear characteristic of the laser single spectral line of the measured gas by using an absorption spectrum measuring method, and establishing the relationship between the absorbance and the pressure and the temperature:
wherein A is the absorbance, C is the gas volume ratio, S (T) is the linear intensity of the absorption line as a function of the temperature T, and L is the effective length of the gas chamber;
step three, simultaneously establishing a formula (1) and a formula (3), eliminating the temperature T, and obtaining an equation only related to the pressure p as follows:
S-1[A/(pCL)]=p/ρR[1+Bρρ+Cρρ2+Dρρ3+...] (4)
in the formula S-1Is an inverse function of the line intensity s (t) of the absorption line, and an accurate pressure value is obtained by solving this equation.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011411248.9A CN112484905B (en) | 2020-12-04 | 2020-12-04 | High-precision pressure optical measurement method in variable temperature environment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202011411248.9A CN112484905B (en) | 2020-12-04 | 2020-12-04 | High-precision pressure optical measurement method in variable temperature environment |
Publications (2)
Publication Number | Publication Date |
---|---|
CN112484905A CN112484905A (en) | 2021-03-12 |
CN112484905B true CN112484905B (en) | 2022-03-29 |
Family
ID=74939540
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202011411248.9A Active CN112484905B (en) | 2020-12-04 | 2020-12-04 | High-precision pressure optical measurement method in variable temperature environment |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN112484905B (en) |
Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0283047A2 (en) * | 1987-03-19 | 1988-09-21 | Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. | Method and device for contactless aquisition of data for the spatial resolution of density and temperature in a volume sample |
CN1916667A (en) * | 2005-08-17 | 2007-02-21 | 富士胶片株式会社 | Optical resin film and polarizing film and liquid crystal display device using the same |
CN101324443A (en) * | 2008-07-30 | 2008-12-17 | 哈尔滨工程大学 | Space division multiplexing Mach-Zehnder cascade type optical fiber interferometer and measurement method thereof |
CN101945940A (en) * | 2007-12-20 | 2011-01-12 | 埃克森美孚研究工程公司 | Polypropylene ethylene-propylene copolymer blend and produce it at line method |
DE102011005834A1 (en) * | 2011-03-21 | 2012-06-14 | Innovent E.V. | Monitoring plasma or flame at atmospheric pressure, comprises measuring optical emission of plasma or flame by spectrometer and determining based on characteristics of plasma or flame, and using intensity-calibrated spectrometer |
CN103941331A (en) * | 2014-05-07 | 2014-07-23 | 江苏亨通光纤科技有限公司 | Polyimide coated optical fiber and machining process thereof |
CN104535008A (en) * | 2014-12-15 | 2015-04-22 | 哈尔滨工程大学 | Low-coherence optical fiber distortion sensor network demodulating system based on Smith resonance interference type optical path matching scanner |
CN104995145A (en) * | 2013-02-20 | 2015-10-21 | 赫罗伊斯石英玻璃股份有限两合公司 | Optical component made of quartz glass for use in arf excimer laser lithography, and method for producing the component |
CN105588661A (en) * | 2015-11-12 | 2016-05-18 | 哈尔滨工程大学 | Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating |
CN106969800A (en) * | 2017-05-03 | 2017-07-21 | 东南大学 | The apparatus and method that a kind of utilization single spectral line measures gas temperature and concentration simultaneously |
CN208350234U (en) * | 2018-04-20 | 2019-01-08 | 鞍山峰澜科技有限公司 | A kind of temperature-compensating sensing device of optical cavity ring-down technology |
CN111061319A (en) * | 2018-10-17 | 2020-04-24 | 北京自动化控制设备研究所 | Atomic gas chamber temperature closed-loop control method based on optical pumping saturation absorption |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101871791B (en) * | 2010-06-30 | 2012-03-14 | 中国人民解放军国防科学技术大学 | Multi-parameter sensor and measurement system based on photonic crystal fiber |
CN110008574B (en) * | 2019-03-29 | 2022-12-13 | 京东方科技集团股份有限公司 | Temperature parameter and pressure parameter acquisition method, device, equipment and storage medium |
-
2020
- 2020-12-04 CN CN202011411248.9A patent/CN112484905B/en active Active
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0283047A2 (en) * | 1987-03-19 | 1988-09-21 | Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. | Method and device for contactless aquisition of data for the spatial resolution of density and temperature in a volume sample |
CN1916667A (en) * | 2005-08-17 | 2007-02-21 | 富士胶片株式会社 | Optical resin film and polarizing film and liquid crystal display device using the same |
CN101945940A (en) * | 2007-12-20 | 2011-01-12 | 埃克森美孚研究工程公司 | Polypropylene ethylene-propylene copolymer blend and produce it at line method |
CN101324443A (en) * | 2008-07-30 | 2008-12-17 | 哈尔滨工程大学 | Space division multiplexing Mach-Zehnder cascade type optical fiber interferometer and measurement method thereof |
DE102011005834A1 (en) * | 2011-03-21 | 2012-06-14 | Innovent E.V. | Monitoring plasma or flame at atmospheric pressure, comprises measuring optical emission of plasma or flame by spectrometer and determining based on characteristics of plasma or flame, and using intensity-calibrated spectrometer |
CN104995145A (en) * | 2013-02-20 | 2015-10-21 | 赫罗伊斯石英玻璃股份有限两合公司 | Optical component made of quartz glass for use in arf excimer laser lithography, and method for producing the component |
CN103941331A (en) * | 2014-05-07 | 2014-07-23 | 江苏亨通光纤科技有限公司 | Polyimide coated optical fiber and machining process thereof |
CN104535008A (en) * | 2014-12-15 | 2015-04-22 | 哈尔滨工程大学 | Low-coherence optical fiber distortion sensor network demodulating system based on Smith resonance interference type optical path matching scanner |
CN105588661A (en) * | 2015-11-12 | 2016-05-18 | 哈尔滨工程大学 | Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating |
CN106969800A (en) * | 2017-05-03 | 2017-07-21 | 东南大学 | The apparatus and method that a kind of utilization single spectral line measures gas temperature and concentration simultaneously |
CN208350234U (en) * | 2018-04-20 | 2019-01-08 | 鞍山峰澜科技有限公司 | A kind of temperature-compensating sensing device of optical cavity ring-down technology |
CN111061319A (en) * | 2018-10-17 | 2020-04-24 | 北京自动化控制设备研究所 | Atomic gas chamber temperature closed-loop control method based on optical pumping saturation absorption |
Non-Patent Citations (3)
Title |
---|
基于激光诱导热光栅光谱技术的气体温度测量研究;李自杰;《CNKI》;20201201;全文 * |
激光干涉测量中光学窗口受动态压力的影响分析;李博等;《振动与冲击》;20200515(第09期);全文 * |
高温高压流场温度激光光谱测量方法研究;张步强;《CNKI》;20190427;全文 * |
Also Published As
Publication number | Publication date |
---|---|
CN112484905A (en) | 2021-03-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107504924B (en) | A kind of wide area value thermal contact resistance ternary test method and device | |
Rieker et al. | Rapid measurements of temperature and H2O concentration in IC engines with a spark plug-mounted diode laser sensor | |
US7774171B2 (en) | Methods for optimizing parameters of gas turbine engine components | |
Kirollos et al. | ECAT: an engine component aerothermal facility at the University of Oxford | |
CN105974345B (en) | Free space terminal short circuit complex dielectric permittivity tests system high temperature calibration method | |
CN107462743B (en) | Wind speed calibration device and calibration method suitable for low air pressure | |
Klein | Application of liquid crystals to boundary-layer visualization | |
Aye-Addo et al. | Development of a lifetime pressure sensitive paint procedure for high-pressure vane testing | |
Siddiqui et al. | Measurement of wall-cooling effects on hypersonic boundary-layer transition using focused laser differential interferometry | |
CN112484905B (en) | High-precision pressure optical measurement method in variable temperature environment | |
CN110470871A (en) | Based on the multi-mode material electromagnetic parameter test device and method of single port | |
CN112484783B (en) | Optical-based gas pressure and temperature high-precision synchronous measurement method | |
Siddiqui et al. | Correlated off-body density fluctuations and surface heating in hypersonic boundary layer transition | |
Georgiadis et al. | Mach Number and Heating Effects on Turbulent Supersonic Jets | |
Wernet et al. | Velocity, temperature and density measurements in supersonic jets | |
Markowski et al. | Instrumentation for development of aircraft powerplant components involving fluid flow | |
CN115200874A (en) | Flow testing method for detecting aircraft engine power-driven fuel nozzle product | |
Conti et al. | Schlieren visualizations of non-ideal compressible fluid flows | |
de Bruyn Kops et al. | Re-examining the thermal mixing layer with numerical simulations | |
CN104596757B (en) | Variable geometry turbine supercharger nozzle ring flow calibration method and experimental rig | |
Hilditch et al. | Unsteady heat transfer measurements on a rotating gas turbine blade | |
Henderson | Crossflow transition at Mach 6 on a cone at low angles of attack | |
Wagner et al. | On the directional sensitivity of hot-wires: a new look at an old phenomenon | |
Lee et al. | Performance evaluation of a rake used for measuring total pressure and total temperature inside an engine inlet duct | |
Örlü et al. | The influence of temperature fluctuations on hot-wire measurements in wall-bounded turbulence |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |